Meta-analysis of effects of long-term exposure to PM2.5 on C-reactive protein levels
以“细颗粒物”“大气颗粒物”“C反应蛋白”“Fine Particulate Matter”“PM2.5”“Particulate Air Pollutants”“Ambient Particulate Matter”“CRP”“C-Reactive Protein”“High Sensitivity C-Reactive Protein”为检索词，检索PubMed、Embase、Web of Science、中国知网（CNKI）、万方数据库，纳入自2000年1月1日至2022年1月1日发表的PM2.5长期暴露影响CRP水平的队列研究，提取各项研究中PM2.5浓度每升高10 μg·m−3，CRP水平百分比变化的数据，进行总体meta分析、亚组分析和敏感性分析。
CI：2.24%~18.57%， P<0.05）， І2=84.2%。亚组分析根据PM2.5长期暴露的年平均浓度分组后，<15 μg·m−3和15 μg·m−3 ~组的组内异质性显著减少，亚组分析森林图显示两组之间存在差异。敏感性分析结果显示，7项研究之间存在高度异质性，PM2.5年平均浓度最高的两篇文献为异质性的来源。Egger检验及漏斗图结果提示相关研究无明显发表偏倚。 结论
Fine particulate matter (PM2.5) is a serious air pollutant associated with elevated levels of C-reactive protein (CRP), an inflammatory indicator.
To assess the potential impacts of long-term exposure to PM2.5 on CRP levels based on previous epidemiological studies.
PubMed, Embase, Web of Science, CNKI, and Wanfang databases were searched to screen the cohort studies published from January 1, 2000 to January 1, 2022 on the effects of long-term exposure to PM2.5 on CRP levels. "Fine Particulate Matter", "PM2.5", "Particulate Air Pollutants", "Ambient Particulate Matter", "CRP", "C-reactive Protein", and "High Sensitivity C-reactive Protein" in English or Chinese were the key words used in the search. The percentage change in CRP level per 10 μg·m−3 increase in PM2.5 concentration in each study was extracted, followed by meta-analysis, subgroup analysis, and sensitivity analysis.
A total of 1241 articles were retrieved, and 7 articles were included. Random-effects models were used to merge the included data, and it was found that the percentage of CRP level increased by 10.41% (95%
CI: 2.24%-18.57%, P<0.05), when PM2.5 concentration increased by 10 μg·m−3, І2=84.2%. The subgroup analysis conducted with grouping based on the annual mean concentration of PM2.5 long-term exposure showed that the intra-group heterogeneity was significantly reduced in the <15 μg·m−3 and the 15- μg·m−3 groups, and the subgroup forest analysis showed differences between the two groups. The results of sensitivity analysis showed that there was a high degree of heterogeneity among the 7 studies, and the 2 papers with the highest annual average PM2.5 concentration were the sources of heterogeneity. The Egger test and the funnel plot indicated that no obvious publication bias was found. Conclusion
Long-term exposure to PM2.5 can raise levels of CRP in human body.